Process for capping bottles



Patented Oct. 18, 1949 PRocEss Fon CAPPING Bo'r'rLEs Walter 0. Farrell-, Racine, Wis., assi'gnor toRalnfair, Ino., Racino, Wis., a; corporation of Wisconsn Application December 22, 1945, Serial No. 636,925

1 Claim. (Cl. 18-57) My invention relates to the artV of making. plastic film, more particularly of synthetic resins, and my invention imrolvesV a process by which the formation of a film is accomplished by ,floating a solution of synthetic resirr or other plastic material upon the surface of a body of water, and utilizing the phenomena of interfacial surface tension to spread or.exp'and=.the solution into a film of desired thickness and area.

The accompanying: dzrawi'ng illustrates diagramrnatically means for carrying out the procedure involved in the formation of the film and the removal of the formed film from the surface of the water,

In the drawings, 4

Fig'. 1 is a Vertical section of'a container for the body of water, a fence for controllng the area of the. film, and the orifice member for introducing the solution to the Water surface;

Fig, 2 is a t'op plan view of the apparatus shown in Fig. 1' and illustrating a partially expand'ed forming film;

Fig. 3' is a view'similar' to Fi'g. 1', illustrating the film completely expanded to size;

Fig. 4 is a top plan view thereof; and

Figs. 5, 6, and '7 are views similar to Figs. 1 and 3, illustrating the removal of the film from the surface of the water by transferring it directly to a bottle to form a hood or cap for the bottle.

In the drawings, the thickness of the film is greatly exaggerated for the purposes of illustration, but it is to be understood that in practice the process is especially adaptable to the production of extremely thin elastic film, thinner in fact than can be formed by other known methods.

In carrying out my process, a predetermined quantity of solution of plastic material such as synthetic resins in liquid form or condition is deposited or introduced to the surface I of a body of water 2 maintained in a suitable container or receptacle 3. The solution is introduced to the Water through a small orifiice in a nozzle member 4 preferably positioned in the center of the area of the film to be formed and spaced somewhat above the surface of the water, although it may be projected into the water so as to introduce the solution slightly below the surface thereof. Bodily moving the stream of solution relatively to water surface by moving the nozzle as the stream is ejected from the nozzle breaks up the pool of solution as it contacts with the water surface and facilitates the initiation of the spreading action of the solution on the water surface. Any suitable means may be used for measuring the quanz r ti-ty'of solution-in accordance with the areav and thickness of thefilm to be formed.

From the point of deposit, which preferably is 'c'entrall-y of the`l area, the solution` rapid-ly spreads or expands radia-Hy over the surface of' thewater asa film 5 byvirtue of the` surface tension ofth-e water and solution, as indicated` in Figs. f to 4. The' exten-t to. which the spre-ads i'sl determined by means of' a fence which retard'sor obstructs-V further spreading when the leading edge or margin 6 of' the film reaches the fence. This fence or control device comprises a series of uprig'ht pin'sfl 'I projectingthrough and above the surface of the water and? supported on a ringshaped mountin'g 8`l positioned below the water surface. The fence pins are`v preferab-ly circular in: sectionV and' are spaced apart sufli'ciently to provide collectiyely a restrictionl against spread of the film beyonrdlthem.. They donot, however, present surface forv adhesion to the film marginsufficient to prevent the' removal ofy the film from the water surface In the present illustration, the fence is circular, surrounds the`area, and thus determines the size of the individual film formed.

During the spread of the film and for sufficient period of time thereafter, the film is allowed to dry by the evaporation of the solvent. The rapidity of drying can be varied and regulated by the thickness, solvents used, and solids concentration of the solution, and by the temperature of the water upon which the film is fioated, and o can be made a matter of seconds where individual films are to be rapidly produced for such purposes as application to bottles as seal caps or hoods.

The removal of the film from the surface of the water after it has dried and solidified to the eX- tent that it can be handled, may be accomplished in various ways. The formed film may be used a-s a hood or seal cap for milk bottles, and in the drawings the application of the film to a bottle A is utilized as the method for removal of the formed film from the water surface. The film is transferred and applied to the bottle by inverting the bottle A, centering it over the film, and plunging it downwardly into the water a sufficient depth to submerge the film in the water. The nozzle 4, of course, is moved out of the way While the bottle is being lowered. The bottle, the neck portion of which is shown in the drawings, is a standard type of milk bottle having a bead or lip Il) surrounding the end. Fig. 3 shows the inverted bottle with its beaded mouth adiacent the film on the Water surface and about to start downwardly into the water, carrying the film with it. Figs. 5, 6, and 7 illustrate the progress of the bottle downwardly into the water and the forming of the film to the contour of the bead and the adjacent neck portion of the bottle. As the bottle moves downwardly, carrying the film with it, pressure of the water beneath the film forces the film into intimate contact with the bead and neck portion of the bottle and causes it to conform to the contour of the bottle and form a sea] or hood over the opening and neck portion of the bottle. The film adheres to the bottle surface and remains in that condition upon the Withdrawal of the bottle from the water. Thus the removal of the film fromithe Water surface is accomplished in the operation of applying the film to the use for which it is intended.

Film may be formed by this process of any materials which Will float and spread or `expand' upon the surface of a body of water by surface tension and solidify so that it can be removed from said surface and handled or used for Whatever purpose intended. Any of the synthetic resins, especially the Vinylite V resins, which are effective film-forming material, may be used. The resins are dissolved in suitable solvents, such as methyl ethyl and methyl isobutyl ketone, cyclohexanone or acetone, to form a liquid solution having the viscosity which enables the solution to spread eifectively'on the water surface,-

and having a density which enables the solution to float.

The physical properties of the resultant film, such as toughness, tensile strength, elasticity, fiexibility, transparency, and adhesion, can be obtained by the used of plasticizers, lubricants and pigment or dyes in the solution. Plasticizers of the Chemical solvent type, the oil type, the resinous type, or suitable synthetic rubber type, may be used to obtain the desired physical properties of the film. Of the chemical solvent type, the most effective are dioctyl phthalate, butyl phthalyl, butyl glycollate, and tricresyl phosphate. Of the lubricants, the most effective are calcium stearate, stearic acid, and oleic acid.

I have found that a film suitable for the hooding or capping of milk bottles hereinbefore referred to, is obtained by a solution of 20% solids and solvents. Of the 20% solids, Vinylite VYI-II-I resins comprise parts, tricresyl phosphate 46 parts, and stearic acid 4 parts. Of the 80% solvents, equal parts of methyl ethyl, ketone, and acetone are used.

The solution is prepared by mixing dry the resin, plasticizers, and lubricants, and then dissolving the mixture in the solvents with agitation and heated at reflux until solvated.

I claim:

The process of capping bottles which consists in depositing a quantity of plastic material in liquid form upon the surface of a body of water, allowing the material to spread in a film upon the water surface, confining the spreading of the material to a given area, and then placing the end of the bottle in contact With the film and forming the film into contact with the bottle surface and forcing the film below the water surface by lowering the end portion of the bottle into the water.

WALTER O. FARRELL.

REFEREN CES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 512,713 Kennedy Jan. 16, 1894 826,781 Gregory July 24, 1906 1,502,803 Weber July 29, 1924 1,520,940 Dulitz Dec. 20, 1924 1,837,854 Esselen Dec. 22, 1931 1,920,118 Walsh et a] July 25, 1933 2,041,143 Olson May 19, 1936 

